package com.angus.alilang.filter;

import com.alibaba.fastjson.JSON;
import com.angus.alilang.common.BaseContext;
import com.angus.alilang.common.R;
import lombok.extern.slf4j.Slf4j;
import org.springframework.util.AntPathMatcher;

import javax.servlet.*;
import javax.servlet.annotation.WebFilter;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;

/**
 * Description :检查用户是否完成登录
 * Created by Angus on 2022/7/12 21:56
 */
@Slf4j
@WebFilter(filterName = "loginCheckFilter",urlPatterns = "/*")
public class LoginCheckFilter implements Filter {
    //路径匹配器，支持通配符
    public static final AntPathMatcher PATH_MATCHER = new AntPathMatcher();

    @Override
    public void doFilter(ServletRequest servletRequest, ServletResponse servletResponse, FilterChain filterChain) throws IOException, ServletException {
        HttpServletRequest request = (HttpServletRequest) servletRequest;
        HttpServletResponse response = (HttpServletResponse) servletResponse;

        //1.获得本次请求的URI
        String requestURI = request.getRequestURI();

        log.info("拦截到请求：{}",requestURI);

        //定义不需要处理的请求路径
        String[] urls = new String[]{
                "/employee/login",
                "/employee/logout",
                "/backend/**",
                "/front/**",
                "/common/**",
                "/user/sendMsg",
                "/user/login"
        };

        //2.判断请求是否需要处理
        boolean check = check(urls, requestURI);

        //3.如果不需要处理，则直接放行
        if(check) {

            log.info("本次请求{}不需要处理",requestURI);

            filterChain.doFilter(request, response);
            return;
        }

        //4-1.判断登录状态，如果已经登陆，则直接放行
        if(request.getSession().getAttribute("employee") != null){

            log.info("用户已经登陆，id为：{}",request.getSession().getAttribute("employee"));

            Long empId = (Long) request.getSession().getAttribute("employee");
            BaseContext.setCurrentId(empId);

            filterChain.doFilter(request, response);
            return;
        }


        //4-2.判断登录状态，如果已经登陆，则直接放行  --(移动端）
        if(request.getSession().getAttribute("user") != null){

            log.info("用户已经登陆，id为：{}",request.getSession().getAttribute("user"));

            Long userId = (Long) request.getSession().getAttribute("user");
            BaseContext.setCurrentId(userId);

            filterChain.doFilter(request, response);
            return;
        }

        log.info("用户未登录");
        //5.如果未登录则返回未登录结果,通过输出流方式向客户端页面响应数据
        response.getWriter().write(JSON.toJSONString(R.error("NOTLOGIN")));
        return;
    }

    /**
     * 路径匹配，，
     * @param requestURI
     * @return
     */
    public boolean check(String[] urls,String requestURI) {
        for (String url : urls) {
            boolean match = PATH_MATCHER.match(url, requestURI);
            if(match) {
                return true;
            }
        }
        return false;
    }
}
